Vehicles that utilize an inverted pendulum attitude control (hereinafter simply referred to as “inverted pendulum vehicles”) have been drawing attention in recent years. For example, Patent Document 1 (Japanese Patent Application Publication No. JP-A-2004-129435) proposes a conveying apparatus that utilizes an inverted pendulum attitude control.
Meanwhile, conventional automatic driving systems are known that automatically drive a vehicle such as an automobile. Under such automatic driving systems, it is often more preferable for a plurality of automobiles traveling on an expressway or the like to form a line and travel as a vehicle group rather than as individual vehicles from the standpoints of saving labor, mitigating traffic, and the like. Therefore, various research has been carried out regarding how following vehicles form a line with respect to a preceding vehicle and to what extent follow-up running is automatically performed with respect to a preceding vehicle in automatic driving systems. Art related to such follow-up running is described in Patent Document 2 (Japanese Patent Application Publication No. JP-A-2001-273588), for example.    Patent Document 1: Japanese Patent Application Publication No. JP-A-2004-129435    Patent Document 2: Japanese Patent Application Publication No. JP-A-2001-273588